Vitelity INBOUND and SOURCE ID parameters?

I thought I would split this topic from the intial Vitelity topic I posted.....

Under the 'Source ID' tab, We have the source identification by DID checked off. We have entered our DID numbers for our routing. We are not sure about the 'SIP Field containing DID numbers' field. We are having some issues where the calls are not coming in. Currently, the setting we have is 'Request Line URI:User Part'. Also, not sure about what parameters should be in the 'Inbound Parameters' tab? Currently, they are just defaults.

Just thought I would throw that post out there. I have tried some of the defaults and there are some still some issues with calls not getting through. I will keep trolling for any other solutions and will post if I find something different.